This ProBuilder code snippet demonstrates how to implement a dynamic money management strategy that adjusts based on trading performance and a system quit mechanism triggered by a specified percentage drawdown from the maximum equity. The code is designed to switch between different money management types and halt trading if the equity falls significantly.

Capital = 10000
MinSize = 1
MM1stType = 0
MM2ndType = 1
TradesQtyForSwitch = 50
ProfitNeededForSwitch = 3
DrawdownNeededToSwitch = 10
DrawdownNeededToQuit = 35
Once MoneyManagement = MM1stType
Equity = Capital + StrategyProfit
maxequity = max(equity,maxequity)
if equity < maxequity * (1 - (DrawdownNeededToSwitch/100)) then
    enoughtrades = 0
    tradecount = 0
    moneymanagement = MM1stType
endif
if equity < maxequity * (1 - (DrawdownNeededToQuit/100)) then
    quit
endif
if not EnoughTrades then
    if abs(countofposition) > abs(countofposition[1]) then
        tradecount = tradecount + 1
    endif
    if tradecount > TradesQtyForSwitch and maxequity >= Capital * (1 + (ProfitNeededForSwitch/100)) then
        EnoughTrades = 1
        MoneyManagement = MM2ndType
    endif
endif
IF MoneyManagement = 1 THEN
    PositionSize = Max(MinSize, Equity * (MinSize/Capital))
ENDIF
IF MoneyManagement = 2 THEN
    PositionSize = Max(LastSize, Equity * (MinSize/Capital))
    LastSize = PositionSize
ENDIF
IF MoneyManagement <> 1 and MoneyManagement <> 2 THEN
    PositionSize = MinSize
ENDIF
PositionSize = Round(PositionSize*100)
PositionSize = PositionSize/100
PositionSizeLong = 1 * positionsize
PositionSizeShort = 1 * positionsize

The code snippet above is structured to manage trading risk and adjust position sizes based on the performance of the trading strategy. Here’s a step-by-step explanation:

• Initialization of Variables: Sets initial capital, minimum position size, and types of money management strategies.
• Dynamic Equity Calculation: Updates the equity based on capital and strategy profits and tracks the maximum equity reached.
• Money Management Switch: If the equity drops below a certain percentage from the maximum equity, it switches back to the initial money management type.
• Quit Condition: Stops the trading strategy if the equity falls by a specified percentage from the maximum equity, indicating a significant drawdown.
• Trade Counting: Counts the number of trades to determine when enough trades have been made to consider switching to a more aggressive money management type.
• Position Size Adjustment: Adjusts the position size based on the current money management strategy, ensuring it does not fall below the minimum size.

This approach helps in managing trading risk by dynamically adjusting the investment size and provides a mechanism to stop trading to prevent further losses in a significant drawdown scenario.